Laser cooling of Positronium

Context

An international team of physicists from the Anti-hydrogen Experiment: Gravity, Interferometry, Spectroscopy (AEgIS) collaboration has recently achieved a breakthrough by demonstrating the laser cooling of Positronium.

About

• Physicists representing the Antihydrogen Experiment: Gravity, Interferometry, Spectroscopy (AEgIS) collaboration introduced this scientific success.
• AEgIS is a collaboration of physicists from 19 European and one Indian research group.
• The primary scientific goal of the AEgIS is the direct measurement of the Earth’s gravitational acceleration based on antihydrogen.

The experiment

• The experiment was achieved at the European Organization for Nuclear Research, more popularly referred to as CERN, in Geneva. 
• Experimentalists carried out laser cooling of Positronium atoms first of all from ~380 Kelvin to ~170 Kelvin, and demonstrated the cooling in one dimension using a 70-nanosecond pulse of the alexandrite-based laser system. 
• The lasers deployed, researchers said, have been both within the deep ultraviolet or in the infrared frequency bands.

Note

• Positronium, comprising a certain electron ( e- ) and positron ( e  ), is a fundamental atomic system. 

• Due to its very short life, it annihilates with a half life of 142 nano-seconds. 

• Its mass is twice the electron mass and enjoys the particular distinction of being a pure leptonic atom.

• This hydrogen-like system, with halved frequencies for excitation, makes it an incredible contender for trying laser cooling and thereby performing checks of essential theories in physics.

Significance

• This is an important precursor experiment to the formation of antiHydrogen and the size of Earth’s gravitational acceleration on antihydrogen in the AEgIS experiment. 
• In addition, this scientific feat should open potential possibilities to supply a gamma-ray laser that might subsequently permit researchers to look inside the atomic nucleus and have applications beyond physics.
• This experiment will pave the way for acting spectroscopic comparisons required for the Quantum Electrodynamics (QED), the examination of the light and its interplay with charged count number, and a likely degenerate gas of Positronium down the street.
• According to CERN, the new scientific development will allow excessive-precision measurements of the properties and gravitational behaviour of this uncommon yet simple rely–antimatter system, that could screen more modern physics. 
• It additionally lets in the manufacturing of a positronium Bose–Einstein condensate, wherein all ingredients occupy the same quantum state.
• Such a condensate has been proposed as a candidate to supply coherent gamma-ray mild made of monochromatic waves which have a constant phase difference between them.

Source: The Indian Express

UPSC Prelims Practice Question:

Q.The efforts to detect the existence of the Higgs boson particle have become frequent news in the recent past. What is/are the importance of discovering this particle?

1. It will enable us to understand why elementary particles have mass.
2. It will enable us in the near future to develop the technology of transferring matter from one point to another without traversing the physical space between them.
3. It will enable us to create better fuels for nuclear fission.

Select the correct answer using the codes given below:

a. 1 only

b. 2 and 3 only

c. 1 and 3 only

c. 1, 2 and 3

Ans: “a”

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